Internal combustion engine scavenging blower and load driving arrangement



June 27, 1967 w. G. LUNDQUIST 3,327,693

INTERNAL COMBUSTION ENGINE SCAVENGING BLOWER AND LOAD DRIVING ARRANGEMENT Filed Sept. 21, 1965 3 Sheets-Sheet l ""flh.

"' HWHI- "WWII.

""Wih "WWI.

INVENTOR. Marv/v 6. wvaau/sr BY W4 WWW/bu, 03, mm?? June 27, 1967 w. G. LUNDQUIST 3,327,693

INTERNAL COMBUSTION ENGINE SCAVENGING BLOWER AND LOAD DRIVING ARRANGEMENT Filed Sept. 21, 1965 5 Sheets-Sheet z INVEN'IOR. Maren 6. (wow/s7- 4%; Mrs Qwae A mvevs June 27. 1967 w. G. LUNDQUIST 3,327,693

INTERNAL COMBUSTION ENGINE SCAVENGING BLOWER AND LOAD DRIVING ARRANGEMENT Filed Sept. 21, 1965 5 Sheets-Sheet 5 .L, .L .4:. i 3

5L INVENTOR. Marc/v6! ((#1090167- i BY waqmwew fl wzia A770? ers United States Patent D f 3,327,693 INTERNAL C(BMBUSTION ENGINE SCAVENGING BLOWER AND LOAD DRIVING ARRANGEMENT Wilton G. Lundqnist, 32 Hollis Drive, Ho Ho Kus, NJ. 07423 Filed Sept. 21, 1965, Ser. No. 488,849 9 Claims. (Cl. 123-65) ABSTRACT OF THE DISCLOSURE An internal combustion piston engine having a substantially cyclic torque variation in combination with a kinetic blower having an impeller member interposed between a main power output member of said engine and a load to be driven by said engine, said kinetic blower having a pressure chamber in communication with the intake manifold of said engine for delivering pressure air for scavenging and charging said engine, torsionally effective means connecting said power output member to said impeller member and means drivingly connecting said power output member to said driven load, said connecting means having such relative torsional rigidities respectively that more of the cyclic acceleration and deceleration torque delivered by said power output member is directed to the impeller than to all other flywheel masses in the system. According to one embodiment, turbine actuating means is provided for imparting prerotation to said impeller member before the same is operably connected to said power output member.

This invention relates to an internal combustion engine of the type in which a kinetic compressor is utilized to introduce a compressed gaseous medium to the cylinders of said engine.

All internal combustion piston engines require a flywheel (disposed between the engine and the driven load) which stores energy during the torque curve peaks and releases it during the torque curve valleys, thus smoothing out the torque variations applied to the driven load. Diesel engines in particular need such flywheels because the torque variations generated by the combustion proc ess is generally greater than that of other engine types. Thus, the flywheel performs a necessary function, but unfortunately it is usually relatively heavy and this is a drawback in almost all cases. Therefore, if the weight of the flywheel could be reduced or eliminated, this would be a significant improvement.

In addition to a flywheel, two cycle engines require some means for supplying air to scavenge and charge the cylinders. Two of the means used for this purpose are (a) centrifugal blowers and (b) axial flow blowers; both of which are kinetic compressors as distinguished from displacement compressors, and as such, have in common high tip-speed impellers, which, although they are light in weight, have large flywheel potential because of their high impeller tip-speeds.

It is the purpose of this invention to utilize the impeller of a kinetic blower in place of a flywheel and thus combine the two functions, i.e. flywheel and blower, in one unit, and thus achieve a notable improvement in two cycle engines in regard to performance, weight and cost. Although the preceding description has been related to two cycle engines which require an air blower of some kind, the broad aspects of the invention would be equally applicable to any two or four cycle engine which employs a kinetic blower supercharger, i.e. either a centrifugal or an axial blower. A further purpose of this invention is to use this impeller flywheel as a means for starting the engine, as will be described later.

Further specific features and advantages of the in- 3,327,693 Patented June 27, 1967 vention will be hereinafter more fully set forth with ref erence to the annexed drawings, showing a presently preferred embodiment of the invention and certain modifications thereof, in which:

FIG. 1 is a top plan view of a multi-cylinder engine showing an embodiment of the present invention;

FIG. 2 is a longitudinal sectional view taken on line 2-2 of FIG. 1, showing somewhat schematically further features of the invention;

FIG. 3 is a view similar to FIG. 2 showing a modification of the invention; and

FIG. 4- is a sectional view taken along the line 4-4 of FIG. 3.

In the embodiment now to be described by way of illustrating the invention, the engine is a two cycle engine shown for simplicity purposes as having an in-line cylinder configuration, but as will be understood by those skilled in the art, the cylinders may be disposed in a V configuration, a radial configuration, or a combination of the same.

Referring to the drawings, and more particularly to FIG. 1, the engine comprises in general a plurality of cylinders such as 1 carried on an engine frame 2 and a centrifugal blower designated in general as 3.

Referring more particularly to FIG. 2, it will be seen that each cylinder such as 1 is provided with a piston such as 4 connected in the conventional manner by a wrist pin 5 and a connecting rod 6 to the engine chankshaft 7 which is suitably journaled in the frame 2. The crankshaft 7 has an end 8 on which is rigidly secured a power output gear wheel member 9 in driven mesh with a pinion 10 rigidly fixed to a portion 11 of an output shaft 12 which is suitably journaled for high speed rotation in an anti-friction bearing 13 mounted in the frame 2 and anti-friction means 14 mounted in the blower housing 15. Suitable oil seal means such as 16 is interposed between the blower housing 15 and the power output shaft 12 and the outwardly extending end of the power output shaft 12 carries rigidly secured thereto a centrifugal blower impeller 17. The power output shaft 12 is selectively torsionally rigid for purposes to be more fully described below and is provided with a hollow bore 18 in which is disposed a drive shaft 19 which is substantially less torsionally rigid than the power output shaft 12. The

inner end of the drive shaft 19 is drivingly connected to the power shaft 12 by a spline connection 21) and is provided adjacent its opposite end with a large portion 21 slidably engaged within the bore 18 and provided with an O-ring 22 serving as an oil seal. The extreme outer end of the quill shaft 19 is adapted to be connected to the load to be driven as by a clutch symbolically shown as 23.

The significant feature of the foregoing mechanical arrangement is that the air supply blower impeller 17 is driven by the power output shaft 12 via an appropriately torsionally rigid drive connection to the engine power output member 9 and is functionally interposed as a flywheel between the engine crankshaft and the driven load connected to the less rigid torsional shaft 19. The torsional rigidity of the connection of the impeller to power output member 9 is of such nature that, during the cyclic accelerations and decelerations of the engine (due to the cyclic torque variations previously mentioned), a greater portion of the acceleration and deceleration torque delivered by the engine power output member 9 is directed to the impeller than to all other separate flywheel masses in the system. Accordingly, the blower impeller 17 can therefore function both as a blower and a flywheel. A further advantage of this arrangement is that the gear ratio between the power output gear wheel 9 and the driven pinion 10, and the tip diameter of the impeller 17 are such as to provide a high impeller tipspeed of from 500 feet per second to up wards of 1500 feet per second as compared to conventional flywheel tip speeds of generally less than 200 feet per second, so that the flywheel potential of the blower impeller 17 can be (lb. for lb.) 6 to more than 50 times as great as that of the conventional flywheel. In actual practice, these tip speeds may be related more specifically to the ratio between the tip speed of the impeller 17 and the mean speed of the pistons such as 4, and to acoomplish the objective of this invention, this ratio must beat least 8:1 to assure practical air supply characteristics. For supercharging, this ratio should be substantially higher than 8:1.

It will thus be seen that a very substantial weight reduction is achieved by this invention, as well as a much improved r.p.m. regulation.

An alternate output drive flange for connecting to a driven load may be provided by an axially aligned extension 31 of output drive member 9 without impairing the fiywheel effect of the impeller, provided the previously mentioned cyclic acceleration torque distribution is adhered to in the design.

Referring again to FIG. 2: The centrifugal blower housing 3 is provided with an air intake 24 from which air enters a throat 25 of the impeller 17 and is forced outwardly from the tips of the impeller into a pressure chamber 26 in communication with an air inlet manifold 27 which conducts the pressure air (or fuel air mixture) from the centrifugal blower to the engine cylinders such as 1 by way of piston ported intake openings designated in general as 28, the piston ported openings such as 29 serving as exhaust ports which are in communication with air exhaust manifold 29a. Fuel inlet nozzles such as 30 serve in the present embodiment to introduce fuel into the cylinders such as 1. It is to be understood that although the present engine is indicated as a compression ignition engine, it is contemplated that the features of the invention may be equally utilized in a spark ignition engine.

FIG. 3 illustrates a variation (mentioned previously) of the invention wherein the blower impeller flywheel is also used as a starter. The configuration is generally similar to that shown in FIG. 2 except that a clutch (designated in general as 40) is interposed between the engine and the impeller flywheel so that the impeller can be independently pre-rotated (by external means) to some selected r.p.m. before it is operably connected to the engine by engaging the clutch. By this means, the energy stored in the impeller flywheel can be utilized to crank the engine for starting. Once the cranking operation has been started by engaging the clutch, the external energizing of the impeller may be continued to continue the cranking of the engine until it begins to operate under its own power.

The external source of power to pre-rotate the impeller can be some type of motor, either electric or otherwise. Alternatively, the impeller itself can be used as a turbine wheel and thus pre-rotated by appropriate application of some type of working fluid such as compressed air or some other kind of pressurized gas introduced through appropriately designed nozzle passages. It is also a purpose of this invention to provide a novel means for accomplishing the turbine drive function, as will be more particularly pointed out below. It is to be noted that in order to simplify the description of FIG. 3, those parts thereof which are common to FIG. 2 will be designated with the same reference characters to which will be added a prime suflix.

Referring to FIG. 3: An output shaft pinion is operably connectable to an impeller shaft 12 and an impeller 17' by a clutch designated in general as 40 which is controllably operated by hydraulic fluid introduced in the passage 41. The output drive shaft 1% is connected to a driven load by a conventional clutch such as used in automotive vehicles and symbolically shown as 23'. Thus the impeller 17' can be pre-rotated' before starting the engine by not activating clutch 40 until a suitable pre-selected impeller r.p.m. is attained. Engaging clutch 4i) will then cause the flywheel effect of the impeller to crank the engine. In general, pressure fluid entering passage 41 passes through suitable connecting passages into a hollow bore 18' in which a hydraulic chamber 42 is provided by means of a sealing plug 43 having an O-sealing ring 44 and held in position by a locking ring 45. From the chamber 42 the activating fluid passes through suitably provided passagesinto the brake chamber 46 which forces the clutch members into activating engagement.

Referring now more particularly to FIGS. 3 and 4: Means for utilizing the impeller 1'7 as a turbine for starting purposes will now be described. A nozzle passage 50 (FIG. 4) is provided in the impeller housing and is in communication with a pipe 51 adapted to supply turbine working fluid (compressed air or other pressurized gas) to the nozzle passage 50 from where the working fluid impinges on the tips of the impeller blades in a substantially tangential (in the direction of impeller rotation) direction and then passes through slots 52 which are cut into the back wall of the impeller 17' at the rim. These slots 52 are oriented at an angle to the impeller wall so that they in effect impart an antirotation direction (relative to the impeller) to the exiting working fluid, thus providing a generally impulse type turbine blade passage in connection with the impeller blade tips.

After leaving the impeller blade tip passages, the turbine working fluid can escape either via a blower diffuser passage 53, and thence via the blower chamber 26' and inlet manifold 27' to the engine cylinders such as 1 (as in the previously described embodiment of FIG. 1) or via passages 54 and 55 if the valve 56 is open. Suitable means (not shown) are provided for moving valve 56 to open or closed positions in the direction shown by the arrows. The purpose of this latter escape route is to provide for overboard discharge of the turbine working fluid if either the quantity or the composition of this fluid is such that it would be inadvisable to let it all pass through the engine cylinders.

Having described my invention with particularity with reference to the preferred embodiment of the same, and having referred to some of the possible modifications thereof, it will be obvious to those skilled in the art, after understanding my invention, that other changes and modifications may be made therein without departing from the spirit and scope of the invention and I aim in the appended claims to cover such changes and modifications as are within the scope of the invention.

What I claim is:

1. In an internal combustion piston engine having a substantially cyclic torque variation, the combination of a main power output member, a kinetic blower having an impeller member and a blower pressure chamber, means for conducting pressure air from the blower to the combustion chamber of the engine cylinders for scavenging and charging the engine cylinder, torsionally effective means connecting said impeller member to said power output member, and means for drivingly connecting said power output member to a driven load, said connecting means being of such relative torsional rigidities that more of the cyclic acceleration and deceleration torque delivered by said power output member is directed to the impeller than to all other separate flywheel masses in the system, whereby said impeller is functionally interposed between the main power output member of said engine and said driven load.

2. An engine as set forth in claim 1 in which said blower impeller is mounted on a hollow shaft and adapted to be driven thereby and the means for drivingly connecting said hollow shaft to the driven load comprises a quill shaft disposed within said hollow shaft and drivingly connected thereto.

3. An engine as set forth in claim 1 in which said engine is provided with a crankshaft having fixed thereto an output gear wheel in driving mesh with a substantially smaller pinion gear drivingly connected to said impeller member and in which the gear ratio between said output gear wheel and said driven pinion and the tip diameter of said impeller are such that the impeller has a tip speed of from 500 feet per second to upwards of 1500 feet per second.

4. An engine as set forth in claim 1 in which said engine is provided with a crankshaft having fixed thereto an output gear wheel in driving mesh with a substantially smaller pinion gear drivingly connected to said impeller member, said output gear wheel being provided with an axially aligned extension rotatable therewith and having means for connecting said output gear wheel to a driven load.

5. An engine as set forth in claim 1 in which there are a plurality of cylinders provided with reciprocating pistons operatively connected to a crankshaft, said impeller being rotatably connected to said crankshaft for supplying a compressed gaseous medium to the cylinders of said engine, the ratio between the impeller tip speed and the mean piston speed being at least 8: 1.

6. An internal combustion engine as set forth in claim 5 in which the impeller supplies a supercharging gaseous medium to said cylinders and the ratio between the impeller tip speed and the mean piston speed is substantially greater than 8:1.

7. An internal combustion engine as set forth in claim 1 in which said engine comprises a plurality of cylinders provided with reciprocating pistons operatively connected to said main power output member and the ratio between the impeller tip speed and the mean reciprocating speed and the mean piston speed being at least 8: 1.

8. An internal combustion engine as set forth in claim 1 in which a first clutch is interposed between said power output member and said blower impeller, a second clutch interposed between said power output member and said driven load and means is provided for imparting pre-rotation to said impeller member before said impeller member is operably connected to said power output member by said first clutch means.

9. An internal combustion engine as set forth in claim 1 in which a first clutch is interposed between said power output member and said blower impeller, a second clutch interposed between said power output member and said driven load means is provided for imparting pre-rotation to said impeller member before said impeller member is operably connected to said power output member by said first clutch means, said means for imparting prerotation to said impeller member including means for actuating said impeller as a turbine.

References Cited UNITED STATES PATENTS 1,440,685 1/ 1923 Kroukovsky 123-65 2,176,021 10/ 1939 Grutzner l23--65 2,252,512 8/1941 Keller 123-65 2,255,424 9/1941 Jandasek 123179 2,445,965 7/ 1948 Packwood 12341.65 X 3,253,658 5/1966 Bradley 135.72

FOREIGN PATENTS 696,729 9/ 1953 Great Britain.

CARLTON R. CROYLE, Primary Examiner. WENDELL E. BURNS, Examiner. 

1. IN AN INTERNAL COMBUSTION PISTON ENGINE HAVING A SUBSTANTIALLY CYCLIC TORQUE VARIATION, THE COMBINATION OF A MAIN POWER OUTPUT MEMBER, A KINETIC BLOWER HAVING AN IMPELLER MEMBER AND A BLOWER PRESSURE CHAMBER, MEANS FOR CONDUCTING PRESSURE AIR FROM THE BLOWER TO THE COMBUSTION CHAMBER OF THE ENGINE CYLINDERS FOR SCAVENGING AND CHARGING THE ENGINE CYLINDER, TORSIONALLY EFFECTIVE MEANS CONNECTING SAID IMPELLER MEMBER TO SAID POWER OUTPUT MEMBER, AND MEANS FOR DRIVINGLY CONNECTING SAID POWER OUTPUT MEMBER TO A DRIVE LOAD, SAID CONNECTING MEANS BEING OF SUCH RELATIVE TORSIONAL RIGIDITIES THAT MORE OF THE CYCLIC ACCELERATION AND DECELERATION TORQUE DELIVERED BY SAID POWER OUTPUT MEMBER IS DIRECTED TO THE IMPELLER THAN TO ALL OTHER SEPARATE FLYWHEEL MASSES IN THE SYSTEM, WHEREBY SAID IMPELLER IS FUNCTIONALLY INTERPOSED BETWEEN THE MAIN POWER OUTPUT MEMBER OF SAID ENGINE AND SAID DRIVEN LOAD. 